This proposal is submitted to help organize and conduct the 1987 Gordon Conference on Calcium Phosphates, to be held June 22-26 at Plymouth State College, Plymouth, New Hampshire. This meeting is the eighth in a continuous series and allows the interaction of approximately 120 international scientists from universities, government, and industry who study chemistry, physics, dentistry, medicine, oceanography, geology, soil science, biomaterials, environmental science, and related fields and share a common interest in calcium phosphate research. The general theme for the 1987 Conference is "The Effect of Environmental Systems on Calcium Phosphates," and topics planned for discussion include the structure and physical- chemistry of calcium phosphates; chemical effects on calcium phosphates and demineralization/remineralization processes; biological matrix-mineral interactions dealing with organic and inorganic association at the cellular and molecular levels, calcium transport, and other topics appropriate to biomineralization; biomaterials development, concerning aspects of the use of decalcified bone matrix as implant material for repair of skeletal defects, new approaches to prosthetic devices, and progress in development of heart valves which are non-thrombogenic and inhibit formation of calcium phosphate deposition; gravity effects on bone in man and animal, addressing loss of bone during protracted space and underwater living; genetic engineering of mineral and matrix, concerned with dissolution of calcium phosphates by genetically altered bacteria; and electromagnetic, mechanical, and other effects on biological calcium phosphate deposition, again in bone growth. The strength of this conference lies in the fact scientist with highly diverse backgrounds bring their expertise together to exchange scientific information, and generate, often collaboratively as a direct result of the Conference, new approaches for research solutions to problems in all areas of calcium phosphate studies. The meeting thereby contributes to scientific cooperation and understanding between laboratories both within and outside this country.